There are more and more varieties of existing portable and visible electric products, such as the palmtop computer, mini-TV and palmtop recorder and players like MP4, etc. as well as DVD players. These portable and visible electric products require flexible movement and convenient portability and use anywhere at any time. They are very popular and are especially suitable for applications in mobile vehicles, such as automobiles, aeroplanes and steamships. This makes it easy for people to entertain or work during their trips. However, such visible electric products currently require that they be handheld and this may make it inconvenient during long-time use. Furthermore, it is difficult to manage to hold them in ones hands, and it is thus possible for the products to fall off and be damaged. It is thus necessary particularly for use in mobile vehicles to design a mounting unit suitable for such products to make them readily affixable and easily adjustable.